[sdiy] Two unrelated questions: Switch loads, debouncing

[Richard Wentk]

On 8 Jan 2009, at 14:35, flightofharmony wrote:

> Hello all,
>
> Looking for some input on two questions that have been nagging me  
> of late.
>
> 1) Most switches are specified for resistive loads only, as  
> capacitive loads
> can quickly weld or vaporize the contacts. The question: where is the
> general threshold for this?

Generally all you need to do is make sure the reactive surge current  
is less than the switch's rating. You can guesstimate the surge  
current from first principles, and add a current limiting resistor to  
make sure it's never exceeded.

> 2) This popped into my head the other day: Is there any reason to  
> add switch
> debouncing in entirely analog circuits?

Depends on the circuit. If you're switching a signal path, then yes,  
you want to add some debouncing/filtering to avoid crackles and clicks.

Richard